A great way when moving your equipment to a new location, new router/switch etc to help confirm what MAC has what IP:
for ip in `arp -na|awk '{print $2}'|sed s/\(//g|sed s/\)//g`; do
echo ping $ip
ping -c 1 -w 1 $ip > /dev/null
if [ "$?" == 0 ]; then
echo "$ip UP"
fi
done
linux, bash, pinga, router, etc, ip, arp, na, awk, sed, echo, ping, dev, null, quot, fi,